BMW turns its engineers loose to slash energy use

For automakers in North America, the migration to electrical systems and accessories such as stop-start, regenerative brakes, electric pumps and electric power steering is starting to look like a stampede.

What's next? One place to look is BMW AG.

BMW wants to coax as much power as possible from a gallon of gasoline -- and protect its performance image in an era of rising fuel-economy standards. So its engineers are searching for high-tech ways to conserve energy.

For instance, BMW is developing an intelligent engine control unit that uses the vehicle's navigation system to more efficiently regulate functions such as battery recharging and engine cooling.

The concept is called "predictive engine management," said Tom Baloga, vice president of engineering for BMW of North America Inc.

The concept works best for motorists on regular daily commutes. After the driver enters a destination into the navigation system, the computer calculates the locations of hills, high-speed highways and low-speed city streets.

The computer might plan to recharge the battery during an extended downhill stretch when less of the engine's power is needed.

Or if the motorist is going to enter a highway on-ramp in a mile or two, the engine management system might boost the flow of engine coolant in advance.

"We are really excited about this," Baloga said. "The vehicle will know from the map what kinds of hills and highway stretches you will experience. We are very close to offering this in production."

BMW also is working on a device that would capture waste heat from the exhaust and convert it into electricity. Thus, the starter battery would get recharged as the vehicle accelerates -- when the exhaust runs hottest.

Another trend to watch: steer-by-wire, electronic steering that eliminates the mechanical link between the steering column and the vehicle's wheels. Current versions of electric power steering maintain the mechanical link.

Steer-by-wire, Baloga said, "is certainly something that is very actively pursued by many companies."

These improvements are costly. BMW has spent $1.5 billion to develop fuel-saving technologies such as stop-start, regenerative brakes and electric power steering, Baloga said.

"We are at the point where we have to dig very deep to get the necessary efficiency gains," he said. "The low-hanging fruit has been picked."